Method and Device for Determining Indication Signalling of Pilot Signal for Channel Measurement and Method and Device for Feeding Back CSI

ABSTRACT

Provided are a method and device for determining indication signalling of a pilot signal for channel measurement, and method and device for feeding back CSI. The method for determining indication signalling of pilot signal for channel measurement includes: a NodeB sends DL control signalling, which includes transmission resource configuration information of a non-periodic CSI-RS, to a terminal, wherein the transmission resource configuration information of the non-periodic CSI-RS is used for determining a location of the non-periodic CSI-RS, and the non-periodic CSI-RS is used for instructing the terminal to perform channel measurement. The non-periodic CSI-RS is determined according to the transmission resource configuration information of the non-periodic CSI-RS, and channel measurement is further performed according to the non-periodic CSI-RS, so that the problems of higher overhead and resource waste caused by periodical sending of a CSI-RS in the related art may be solved, resources are saved, and sending overhead is reduced.

TECHNICAL FIELD

The present disclosure relates to the field of communications, and inparticular to a method and device for determining indication signallingof a pilot signal for channel measurement, and a method and device forfeeding back Channel State Information (CSI).

BACKGROUND

In a wireless communication system, a sender and a receiver achievehigher rates in a spatial multiplexing manner by virtue of multipleantennae. The receiver needs to perform channel measurement according toa pilot signal sent by the sender and feeds back channel information tothe sender, and the sender uses some sending pre-coding technologiesaccording to obtained CSI to greatly improve transmission performance Ina Long Term Evolution (LTE) system, channel information is obtained bymeasuring and estimating channel according to a Cell specific ReferenceSignal (CRS) or a Channel State Information Reference Signal (CSI-RS).In a newer protocol version, CSI-RS-based channel measurement is mainlyadopted.

In a related art, a NodeB may periodically send one or more sets ofCSI-RSs, and a terminal uses these CSI-RSs for channel measurement, andthen feeds back CSI to the NodeB. The CSI-RS is significant forperformance of a Multiple Input Multiple Output (MIMO) system.Generally, each antenna sends one channel measurement pilot signal.Locations of channel measurement pilot signals sent by differentantennae in the time and frequency domains or the code domain arestaggered, and may be kept orthogonal without mutual interference, andeach antenna corresponds to one CSI-RS port. The terminal may measurephysical channels between its receiving antennae and sending antennae ata receiver, thereby obtaining an Nr*Nt channel matrix, wherein Nr is thenumber of the receiving antennae, and Nt is the number of the sendingantennae.

A location of a subframe for sending a CSI-RS in the time domain and alocation of a Resource Element (RE) in the subframe are introducedbelow. In the time domain, a channel may not be suddenly changed, andeach subframe is only 1 ms, so that it is unnecessary to send allsubframes. A CSI-RS may be shared by all User Equipment (UE), so thatthe CSI-RS is periodically sent under a normal circumstance. Regulationsin standard 36.211 of LTE are shown in Table 1, i.e. CSI-RS subframeconfiguration.

TABLE 1 CSI-RS CSI-RS subframe offset CSI-RS-SubframeConfig periodicityT_(CSI-RS) Delta_(CSI-RS) I_(CSI-RS) (subframes) (subframes) 0-4 5I_(CSI-RS)  5-14 10 I_(CSI-RS)-5 15-34 20 I_(CSI-RS)-15 35-74 40I_(CSI-RS-)35  75-154 80 I_(CSI-RS)-75

In table 1, I_(CSI-RS) is a configuration parameter of a CSI-RS, and isvalued from 0 to 154, and different values may correspond to differentCSI-RS periodicities and subframe offsets. FIG. 1 is a diagram oflocations of subframes corresponding to a part of CSI-RS configurationexamples, the subframe locations corresponding to the configurations ofI_(CSI-RS)=0, I_(CSI-RS)=2 and I_(CSI-RS)=5 respectively.

At a frequency-domain location, there is a CSI-RS in each PhysicalResource Block (PRB) pair, and a sending pattern of the same port indifferent PRB pairs is the same. A pattern of a CSI-RS is shown in FIG.2. A PRB pair may refer to a regulation in LTE protocol 36.211, and atypical condition includes 12 frequency-domain subcarriers and 14time-domain Orthogonal Frequency Division Multiplexing (OFDM) symbols.

An LTE system defines that 40 REs in one PRB pair may be used as CSI-RSsand are divided into 5 patterns, and each pattern includes 8 REs, asshown in the FIG. 1. Each port of the CSI-RS averagely occupies one REin one PRB pair, and all the ports belonging to the same CSI-RS resourceare required to be limited in one pattern. At present, one set ofCSI-RSs may support maximally 8 ports, so that there are five locationcandidates when the number of the ports is 8, there are 10 configurablelocations when the number of the ports is 4 and there are 20configurations when the number of the ports is 2.

In the related art, a CSI-RS is a Cell/Transmission Point (TP) specificdesign, a NodeB is not allowed to perform pre-coding processing whensending a CSI-RS, and it is mainly because the CSI-RS is shared bymultiple pieces of UE in a cell, the CSI-RS may be pre-coded onlyaccording to a characteristic of a channel between the NodeB to onepiece of UE if it is necessary to pre-code the CSI-RS, which may causeinfluence on the measurement of the other UE and disable the other UE toaccurately measure physical channels between Nr receiving antennae andNt sending antennae, and pre-coding according to characteristics ofchannels of the other UE may make it impossible to accurately calculateand report own CSI.

In addition, the CSI-RS is periodically sent in the related art. Atpresent, maximally 8 antennae are supported, so that overhead in theCSI-RS is not so high. However, for a condition of more antennae, pilotoverhead of such a method may be greatly increased along withmultiplication of the number of the antennae, which may cause influenceon spectrum efficiency of a system.

Moreover, corresponding to a high-dimensional CSI-RS, CSI calculationmay be more complex, terminal complexity is high and time consumption inCSI calculation is higher.

Therefore, the following major problems exist in the related art: aCSI-RS is periodically sent, so that overhead is higher, and resourcesare wasted; the CSI-RS is cell/TP specific, so that pre-coding is notallowed, and the number of ports may not further be effectively reduced;and when there are more antennae, the overhead is high, and CSI feedbackis large in calculation amount and high in complexity.

SUMMARY

The embodiments of the present disclosure provide a method and devicefor determining indication signalling of a pilot signal for channelmeasurement, a method and device for triggering Channel StateInformation (CSI) feedback and a method and device for feeding back CSI,so as to at least solve the problems of higher overhead and resourcewaste caused by periodical sending of a CSI-RS in the related art.

According to one aspect of the embodiments of the present disclosure, amethod for determining indication signalling of a pilot signal forchannel measurement is provided, which includes that: a NodeB sendsDownlink (DL) control signalling, which includes transmission resourceconfiguration information of a non-periodic CSI-RS, to a terminal,wherein the transmission resource configuration information of thenon-periodic CSI-RS is used for determining a location of thenon-periodic CSI-RS, and the non-periodic CSI-RS is used for instructingthe terminal to perform channel measurement.

In an example embodiment, the transmission resource configurationinformation of the non-periodic CSI-RS includes at least one of:information indicating a location of a subframe for sending thenon-periodic CSI-RS, information indicating a location of a PRB pair forsending the non-periodic CSI-RS, information indicating the number ofCSI-RS ports of the non-periodic CSI-RS, and information indicating alocation of RE, which is used for sending the non-periodic CSI-RS, in aPRB pair.

In an example embodiment, the step that the NodeB sends the DL controlsignalling, which includes the transmission resource configurationinformation of the non-periodic CSI-RS, to the terminal includes atleast one of the following steps: the NodeB sends a notice about theinformation indicating the location of the subframe to the terminalthrough physical layer configuration signalling; the NodeB sends anotice about the information indicating the location of the PRB pair tothe terminal through physical layer control signalling; the NodeB sendsa notice about the information indicating the number of the CSI-RS portsto the terminal through physical layer signalling and/or Radio ResourceControl (RRC) signalling; and the NodeB sends a notice about theinformation indicating the location of the RE, which is used for sendingthe non-periodic CSI-RS, in the PRB pair to the terminal through thephysical layer signalling and/or the RRC signalling.

In an example embodiment, a method for determining a location forsending the non-periodic CSI-RS includes: determining the location forsending the non-periodic CSI-RS according to the information indicatingthe location of the subframe carried in the physical layer configurationsignalling received by the terminal and a preset rule.

In an example embodiment, the step that the NodeB sends the notice aboutthe information indicating the location of the PRB pair to the terminalthrough the physical layer control signalling includes that: the NodeBand the terminal preset multiple sets of locations of transmissionResource Blocks (RBs), wherein each of the multiple sets of locations oftransmission RBs corresponds to one RB Group, and one RB Groupcorresponds to a part of state locations of Downlink Control Information(DCI).

In an example embodiment, each of the multiple sets of locations oftransmission RBs includes at least one of: (1) RB1 to RB[M/4]; (2)RB[M/4+1] to RB[M/2]; (3) RB[M/2+1] to RB[3M/4]; (4) RB[3M/4+1] toRB[M]; (5) RB1 to RB[M/2]; (6) RB[M/2+1] to RB[M]; (7) all RBs with oddindex values; (8) all RBs with even indexes; and (9) the latest RBstransmitting a Physical Downlink Shared Channel (PDSCH), wherein M isthe number of PRB pairs corresponding to a current bandwidth.

In an example embodiment, the preset multiple sets of locations oftransmission RBs are specified by a protocol in advance, or the presetmultiple sets of locations of transmission RBs are agreed by the NodeBthrough a high-layer signalling configuration.

In an example embodiment, the number of CSI-RS ports of the non-periodicCSI-RS and the information indicating the location of the RE, which isused for sending the non-periodic CSI-RS, in the PRB pair arejoint-coded.

In an example embodiment, the step that the NodeB sends the DL controlsignalling, which includes the transmission resource configurationinformation of the non-periodic CSI-RS, to the terminal includes that:the NodeB sends the transmission resource configuration information ofthe non-periodic CSI-RS and resource allocation information of a PDSCHto the terminal in the same control signalling format of the DL controlsignalling; or, the NodeB sends the transmission resource configurationinformation of the non-periodic CSI-RS and resource allocationinformation of a Physical Uplink Shared Channel (PUSCH) to the terminalin the same control signalling format of the DL control signalling.

In an example embodiment, the transmission resource configurationinformation of the non-periodic CSI-RS is sent in N preset subframes ofthe DL control signalling, wherein N is an integer more than 1.

According to one aspect of the embodiments of the present disclosure, amethod for triggering CSI feedback is provided, which includes that: aNodeB sends CSI feedback triggering instruction information and resourceallocation information of a PDSCH to a terminal in the same controlsignalling format of DL control signalling, wherein the CSI feedbacktriggering instruction information is used for instructing the terminalto feed back CSI.

In an example embodiment, a manner for setting the CSI feedbacktriggering instruction information includes: setting transmissionresource configuration information of the non-periodic CSI-RS torepresent the CSI feedback triggering instruction information; settingQbit signalling in the control signalling format to represent the CSIfeedback triggering instruction information; or, setting a partial statebit in the control signalling format to represent the CSI feedbacktriggering instruction information.

In an example embodiment, setting the Qbit signalling in the controlsignalling format to represent the CSI feedback triggering instructioninformation includes: setting a state of not triggering CSI acquisition,and setting the other states except the state of not triggering CSIacquisition to represent different rules for triggering acquisition andfeedback.

In an example embodiment, the terminal acquires and/or feeds back theCSI in one of manners as follows: when the CSI feedback triggeringinstruction information triggers CSI feedback, the terminal acquires andfeeds back the CSI on the basis of a periodic CSI-RS or a Cell specificReference Signal (CRS); when the CSI feedback triggering instructioninformation triggers CSI feedback, the terminal acquires and feeds backthe CSI according to a frequency-domain resource where the PDSCHcorresponding to the DL control signalling locates; when the CSIfeedback triggering instruction information triggers CSI feedback, theterminal determines the acquisition and feedback of the CSI according toa feedback mode configured by the DL control signalling; when DL Grantof the DL control signalling triggers CSI feedback, the terminal feedsback the CSI on the Nth subframe after the DL Grant triggers CSIfeedback, wherein N is a natural number more than or equal to 1, and avalue of N is a fixed integer or configured by high-layer signalling;and when the CSI feedback triggering instruction information triggersCSI feedback, the terminal feeds back the CSI at a preset location in asubframe, wherein the preset location includes one of: a Physical UplinkControl Channel (PUCCH) for feedback and a PUSCH for feedback on apreset bandwidth.

In an example embodiment, the step that the terminal acquires and feedsback the CSI according to the frequency-domain resource where the PDSCHcorresponding to the DL control signalling locates includes that: theterminal acquires the CSI on the basis of a Demodulation ReferenceSignal (DMRS) corresponding to the PDSCH.

In an example embodiment, when the terminal feeds back the CSI at thepreset location in the subframe by virtue of the PUCCH, the CSI istransmitted together with Acknowledgement (ACK or A)/Non-Acknowledgement(NACK or N).

According to one aspect of the embodiments of the present disclosure, amethod for feeding back CSI is provided, which includes that: a terminalreceives CSI feedback triggering instruction information from a NodeB,wherein the CSI feedback triggering instruction information and resourceallocation information of a PDSCH are sent in the same controlsignalling format of DL control signalling; and the terminal feeds backCSI acquired according to the CSI feedback triggering instructioninformation to the NodeB.

In an example embodiment, the step that the terminal receives the CSIfeedback triggering instruction information from the NodeB includesthat: the terminal receives transmission resource configurationinformation of the non-periodic CSI-RS from the NodeB; or, the terminalreceives one piece of state information of preset Qbit signalling fromthe NodeB; or, the terminal receives a partial state bit set in thecontrol signalling format from the NodeB.

In an example embodiment, the step that the terminal feeds back the CSIacquired according to the CSI feedback triggering instructioninformation to the NodeB includes one of the following steps: theterminal acquires and feeds back the CSI according to a channelmeasurement pilot at a resource location of a non-periodic CSI-RS,wherein the non-periodic CSI-RS is a signal sent by the NodeB toinstruct the terminal to perform channel measurement; the terminalacquires and feeds back the CSI according to a periodic CRI-RS or a CRS;and the terminal acquires and feeds back the CSI according to afrequency-domain resource where a PDSCH corresponding to DCI locates.

In an example embodiment, the method for feeding back CSI furtherincludes that: the terminal feeds back the CSI on the Nth subframe afterthe CSI feedback triggering instruction information triggers CSIfeedback, wherein N is a natural number more than or equal to 1, and avalue of N is a fixed integer or configured by high-layer signalling;and the terminal feeds back the CSI at a preset location in a subframe,wherein the preset location includes one of: a PUCCH for feedback and aPUSCH for feedback on a preset bandwidth.

In an example embodiment, when the CSI is fed back at the presetlocation in the subframe by a PUCCH, the CSI and A/N are transmittedtogether.

According to one aspect of the embodiments of the present disclosure, adevice for determining indication signalling of a pilot signal forchannel measurement is provided, which is applied to a NodeB andincludes: a first sending component, configured to send DL controlsignalling, which includes transmission resource configurationinformation of the non-periodic CSI-RS, to a terminal, wherein thetransmission resource configuration information of the non-periodicCSI-RS is used for determining a location of the non-periodic CSI-RS,and the non-periodic CSI-RS is used for instructing the terminal toperform channel measurement.

In an example embodiment, the transmission resource configurationinformation of the non-periodic CSI-RS sent by the first sendingcomponent includes at least one of: information indicating a location ofa subframe for sending the non-periodic CSI-RS, information indicating alocation of a PRB pair for sending the non-periodic CSI-RS, informationindicating the number of CSI-RS ports of the non-periodic CSI-RS, andinformation indicating a location of RE, which is used for sending thenon-periodic CSI-RS, in a PRB pair.

In an example embodiment, the first sending component sends the DLcontrol signalling, which includes the transmission resourceconfiguration information of the non-periodic CSI-RS, in at least one ofmanners as follows: sending a notice about the information indicatingthe location of the subframe to the terminal through physical layerconfiguration signalling; sending a notice about the informationindicating the location of the PRB pair to the terminal through physicallayer control signalling; sending a notice about the informationindicating the number of the CSI-RS ports to the terminal throughphysical layer signalling and/or RRC signalling; and sending a noticeabout the information indicating the location of the RE, which is usedfor sending the non-periodic CSI-RS, in the PRB pair to the terminalthrough the physical layer signalling and/or the RRC signalling.

According to one aspect of the embodiments of the present disclosure, adevice for triggering CSI feedback is provided, which is applied to aNodeB and includes: a second sending component, configured to send CSIfeedback triggering instruction information and resource allocationinformation of a PDSCH to a terminal in the same control signallingformat of DL control signalling, wherein the CSI feedback triggeringinstruction information is used for instructing the terminal to feedback CSI.

In an example embodiment, the device further includes a settingcomponent configured to set a representation manner for the CSI feedbacktriggering instruction information, wherein the setting component isconfigured to set the CSI feedback triggering instruction information inone of manners as follows: setting transmission resource configurationinformation of the non-periodic CSI-RS to represent the CSI feedbacktriggering instruction information; setting Qbit signalling in thecontrol signalling format to represent the CSI feedback triggeringinstruction information; and setting a partial state bit in the controlsignalling format to represent the CSI feedback triggering instructioninformation.

According to one aspect of the embodiments of the present disclosure, adevice for feeding back CSI is provided, which is applied to a terminaland includes: a receiving component, configured to receive CSI feedbacktriggering instruction information from a NodeB, wherein the CSIfeedback triggering instruction information and resource allocationinformation of a PDSCH are sent in the same control signalling format ofDL control signalling; and a feedback component, configured to feed backCSI acquired according to the CSI feedback triggering instructioninformation to the NodeB.

In an example embodiment, the receiving component includes: a firstreceiving element, configured to receive transmission resourceconfiguration information of a non-periodic CSI-RS from the NodeB; asecond receiving element, configured to receive one piece of stateinformation of preset Qbit signalling from the NodeB; and a thirdreceiving element, configured to receive a partial state bit set in thecontrol signalling format from the NodeB.

In an example embodiment, the feedback component feeds back the CSIacquired according to the CSI feedback triggering instructioninformation to the NodeB in at least one of manners as follows:acquiring and feeding back the CSI according to a channel measurementpilot at a resource location of a non-periodic CSI-RS, wherein thenon-periodic CSI-RS is a signal sent by the NodeB to instruct theterminal to perform channel measurement; acquiring and feeding back theCSI according to a periodic CM-RS or a CRS; acquiring and feeding backthe CSI according to a frequency-domain resource where a PDSCHcorresponding to DCI locates; feeding back the CSI on the Nth subframeafter the CSI feedback triggering instruction information triggers CSIfeedback, wherein N is a natural number more than or equal to 1, and avalue of N is a fixed integer or configured by high-layer signalling;and feeding back the CSI at a preset location in a subframe, wherein thepreset location includes one of: a PUCCH for feedback and a PUSCH forfeedback on a preset bandwidth.

According to the embodiments of the present disclosure, the followingmethod is adopted: the NodeB sends DL control signalling, which includesthe transmission resource configuration information of the non-periodicCSI-RS, to the terminal, wherein the transmission resource configurationinformation of the non-periodic CSI-RS is used for determination of thelocation of the non-periodic CSI-RS, and the terminal performs channelmeasurement according to the non-periodic CSI-RS. By the embodiments ofthe present disclosure, the non-periodic CSI-RS is determined accordingto the transmission resource configuration information of thenon-periodic CSI-RS, and channel measurement is further performedaccording to the non-periodic CSI-RS, so that the problems of higheroverhead and resource waste caused by periodical sending of a CSI-RS inthe related art may be solved, resources are saved, and sending overheadis reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described here are adopted to provide further understandingof the embodiment of the present disclosure, and form a part of thepresent disclosure. Schematic embodiments of the present disclosure anddescription thereof are adopted to explain the present disclosure andnot intended to form improper limits to the present disclosure. In thedrawings:

FIG. 1 is a diagram of locations of subframes corresponding to a part ofCSI-RS configuration examples according to the related art;

FIG. 2 is a diagram of a pattern of CSI-RS according to the related art;

FIG. 3 is a flowchart of a method for determining indication signallingof pilot signal for measuring channel according to an embodiment of thepresent disclosure;

FIG. 4 is a flowchart of a method for triggering CSI feedback accordingto an embodiment of the present disclosure;

FIG. 5 is a flowchart of a method for feeding back CSI according to anembodiment of the present disclosure;

FIG. 6 is a structure diagram of a device for determining indicationsignalling of pilot signal for channel measurement according to anembodiment of the present disclosure;

FIG. 7 is a first structure diagram of a device for triggering CSIfeedback according to an embodiment of the present disclosure;

FIG. 8 is a second structure diagram of a device for triggering CSIfeedback according to an embodiment of the present disclosure;

FIG. 9 is a structure diagram of a device for feeding back CSI accordingto an embodiment of the present disclosure;

FIG. 10 is a structure diagram of a receiving component of a device forfeeding back CSI according to an embodiment of the present disclosure;

FIG. 11 is a diagram of time-domain locations of a non-periodic CSI-RScorresponding to notification signalling of different locationsaccording to an example embodiment of the present disclosure; and

FIG. 12 is a diagram of additionally developing resources withoutinfluence on configuration of a periodic CSI-RS according to an exampleembodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present disclosure is described below with reference to the drawingsand embodiments in detail. It is important to note that the embodimentsin the present disclosure and characteristics in the embodiments can becombined under the condition of no conflicts.

For the problems of higher overhead and resource waste caused byperiodical sending of the CSI-RS in the related art, the embodiments ofthe present disclosure provide a method for determining indicationsignalling of pilot signal for channel measurement. As shown in FIG. 3,the method is implemented as follows:

a NodeB sends DL control signalling, which includes transmissionresource configuration information of the non-periodic CSI-RS to aterminal, wherein the transmission resource configuration information ofthe non-periodic CSI-RS is used for determining a location of anon-periodic CSI-RS (a channel measurement pilot), and the non-periodicCSI-RS is used for indicating the terminal to perform channelmeasurement.

According to the embodiment of the present disclosure, the non-periodicCSI-RS is determined according to the transmission resourceconfiguration information of the non-periodic CSI-RS, and channelmeasurement is further performed by using the non-periodic CSI-RS, sothat the problems of higher overhead and resource waste caused byperiodical sending of the CSI-RS in the related art may be solved,resources are saved, and sending overhead is reduced.

In an implementation process, there may be multiple pieces oftransmission resource configuration information of the non-periodicCSI-RS, and the transmission resource configuration information of thenon-periodic CSI-RS includes at least one piece of: informationindicating a location of a subframe for sending the non-periodic CSI-RS,information indicating a location of PRB pair for sending thenon-periodic CSI-RS, information indicating the number of ports of thenon-periodic CSI-RS and information indicating a location of RE, whichis used for sending the non-periodic CSI-RS, in a PRB pair.

Regardless of which of the above information that the transmissionresource configuration information of the non-periodic CSI-RS includes,the transmission resource configuration information of the non-periodicCSI-RS may be sent in different forms, then the step that the NodeBsends the DL control signalling, which includes the transmissionresource configuration information of the non-periodic CSI-RS, to theterminal includes any one or more of the following steps:

the NodeB sends a notice about information indicating the location ofthe subframe to the terminal through physical layer configurationsignalling; the NodeB sends a notice about information indicating thelocation of the PRB pair to the terminal through physical layer controlsignalling; the NodeB sends a notice about information indicating thenumber of ports of the CSI-RS to the terminal through physical layersignalling and/or RRC signalling; and the NodeB sends a notice aboutinformation indicating the location of the RE, which is used for sendingthe non-periodic CSI-RS, in the PRB pair to the terminal through thephysical layer signalling and/or the RRC signalling.

The step that the NodeB sends the notice about information indicatingthe location of the PRB pair to the terminal through the physical layercontrol signalling may include the following process: the NodeB and theterminal preset multiple sets of locations of transmission RBs, whereineach of the multiple sets of locations of transmission RBs correspondsto one RB Group, and one RB Group corresponds to a part of statelocations of DCI. Each of the multiple sets of locations of transmissionRBs comprises at least one of: (1) RB1 to RB[M/4]; (2) RB[M/4+1] toRB[M/2]; (3) RB[M/2+1] to RB[3M/4]; (4) RB[3M/4+1] to RB[M]; (5) RB1 toRB[M/2]; (6) RB[M/2+1] to RB[M]; (7) all RBs with odd index values; (8)all RBs with even indexes; and (9) the latest RB transmitting a PDSCH,wherein M is the number of the PRB pairs corresponding to a currentbandwidth. The preset multiple sets of locations of transmission RBs arespecified by a protocol in advance, or the preset multiple sets oflocations of transmission RBs are agreed by the NodeB through ahigh-layer signalling configuration.

In the implementation process, the number of CSI-RS ports of thenon-periodic CSI-RS and the information indicating the location of theRE, which is used for sending the non-periodic CSI-RS, in the PRB pairmay be joint-coded. By such a pre-coding supporting method, the numberof the ports may be effectively reduced, and the calculation amount ofCSI feedback may further be reduced.

After the NodeB sends the transmission resource configurationinformation of the non-periodic CSI-RS, the terminal may determine alocation for sending the non-periodic CSI-RS according to the receivedtransmission resource configuration information of the non-periodicCSI-RS. For example, the terminal may determine the location for sendingthe non-periodic CSI-RS according to the information indicating thelocation of the subframe and a preset rule, wherein the informationindicating the location of the subframe is carried in the physical layerconfiguration signalling received by the terminal.

When the transmission resource configuration information of thenon-periodic CSI-RS is sent, the NodeB may send the transmissionresource configuration information of the non-periodic CSI-RS andresource allocation information of the PDSCH to the terminal in the samecontrol signalling format of the DL control signalling; and the NodeBmay also send the transmission resource configuration information of thenon-periodic CSI-RS and resource allocation information of a PUSCH tothe terminal in the same control signalling format of the DL controlsignalling. When the transmission resource configuration information ofthe non-periodic CSI-RS is sent, the transmission resource configurationinformation of the non-periodic CSI-RS may be sent in N preset subframesof the DL control signalling, for example, the DL control signalling has100 subframes, and the CSI-RS may be sent on the first and secondcontinuous subframes; alternatively, the CSI-RS may also be sent onpreset subframes, for example, on the first subframe, the sixth subframeand the 16th subframe. A value of N is an integer more than 1.

An embodiment further provides a method for triggering CSI feedback, andas shown in FIG. 4, the flow of the method includes the following Step402 to Step 404.

Step 402: a NodeB sets CSI feedback triggering instruction informationand resource allocation information of a PDSCH in the same controlsignalling format of DL control signalling; and

Step 404: the NodeB sends the CSI feedback triggering instructioninformation and the resource allocation information of the PDSCH to aterminal in the same control signalling format of the DL controlsignalling, wherein the CSI feedback triggering instruction informationis used for instructing the terminal to feed back CSI.

There may be multiple manners for setting the CSI feedback triggeringinstruction information, for example, setting transmission resourceconfiguration information of the non-periodic CSI-RS to represent theCSI feedback triggering instruction information; or, setting Qbitsignalling in the control signalling format to represent the CSIfeedback triggering instruction information; or, setting a partial statebit in the control signalling format to represent the CSI feedbacktriggering instruction information. If the Qbit signalling in thecontrol signalling format is set to represent the CSI feedbacktriggering instruction information, a state of not triggering CSIacquisition may be set, and the other states except the state of nottriggering CSI acquisition may be set to represent different rules fortriggering acquisition and feedback.

In an implementation process, the terminal may acquire and feed back theCSI in multiple manners as follows: (1) when the CSI feedback triggeringinstruction information triggers CSI feedback, the terminal acquires andfeeds back the CSI on the basis of a periodic CSI-RS or a CRS; (2) whenthe CSI feedback triggering instruction information triggers CSIfeedback, the terminal acquires and feeds back the CSI according to afrequency-domain resource where the PDSCH corresponding to the DLcontrol signalling locates; (3) when the CSI feedback triggeringinstruction information triggers CSI feedback, the terminal determinesthe acquisition and feedback of the CSI according to a feedback modeconfigured by the DL control signalling; (4) when DL Grant of the DLcontrol signalling triggers CSI feedback, the terminal feeds back theCSI on the Nth subframe after the DL Grant triggers CSI feedback,wherein N is a natural number more than or equal to 1, and a value of Nis a fixed integer or configured by high-layer signalling; and (5) whenthe CSI feedback triggering instruction information triggers CSIfeedback, the terminal feeds back the CSI at a preset location in asubframe, wherein the preset location includes one of: a PUCCH forfeedback and a PUSCH for feedback on a preset bandwidth.

If the terminal acquires and feeds back the CSI according to thefrequency-domain resource where the PDSCH corresponding to the DLcontrol signalling locates, the terminal may acquire the CSI on thebasis of a DMRS corresponding to the PDSCH. If the terminal feeds backthe CSI at the preset location in the subframe by using the PUCCH, theCSI and A/N may be transmitted together.

The embodiment of the present disclosure further provides a method forfeeding back CSI. The method may be executed after CSI feedback istriggered by the method for triggering CSI feedback. As shown in FIG. 5,the flow of the method for feeding back CSI may include the followingStep 502 to Step 504.

Step 502: a terminal receives CSI feedback triggering instructioninformation from a NodeB, wherein the CSI feedback triggeringinstruction information and resource allocation information of a PDSCHare sent in the same control signalling format of DL control signalling;and

Step 504: the terminal feeds back CSI acquired according to the CSIfeedback triggering instruction information to the NodeB.

The terminal may receive the CSI feedback triggering instructioninformation according to different triggering instruction informationsent by the NodeB, for example, the terminal may receive transmissionresource configuration information of the non-periodic CSI-RS from theNodeB; or, the terminal may receive one piece of state information ofpreset Qbit signalling from the NodeB; or, the terminal may receive apartial state bit set in the control signalling format from the NodeB.

In an implementation process, the terminal feeds back the CSI acquiredaccording to the CSI feedback triggering instruction information to theNodeB, and during this procedure, the terminal may acquire and feed backthe CSI in multiple manners, for example, the terminal acquires andfeeds back the CSI in one of manners as follows: (1) the terminalacquires and feeds back the CSI according to a pilot signal for channelmeasurement at a resource location of a non-periodic CSI-RS, wherein thenon-periodic CSI-RS is a signal sent by the NodeB to instruct theterminal to perform channel measurement; (2) the terminal acquires andfeeds back the CSI according to a periodic CRI-RS or a CRS; and (3) theterminal acquires and feeds back the CSI according to a frequency-domainresource where the PDSCH corresponding to DCI locates.

Of course, in the method for feeding back CSI, the CSI may alternativelybe fed back on the Nth subframe after the CSI feedback triggeringinstruction information triggers CSI feedback, wherein N is a naturalnumber more than or equal to 1, and a value of N is a fixed integer orconfigured by high-layer signalling; or, the CSI is fed back at a presetlocation in a subframe, wherein the preset location includes one of: aPUCCH for feedback and a PUSCH for feedback on a preset bandwidth. Whenthe CSI is fed back at the preset location in the subframe by a PUCCH,the CSI and A/N are transmitted together.

The embodiment of the present disclosure further provides a device fordetermining indication signalling of a pilot signal for channelmeasurement. The device may be applied to a NodeB, and its structurediagram is shown in FIG. 6, including: a first sending component 10configured to send DL control signalling, which includes transmissionresource configuration information of a non-periodic CSI-RS, to aterminal, wherein the transmission resource configuration information ofthe non-periodic CSI-RS is used for determining a location of thenon-periodic CSI-RS, and the non-periodic CSI-RS is used for instructingthe terminal to perform channel measurement.

The transmission resource configuration information of the non-periodicCSI-RS sent by the first sending component 10 includes at least onepiece of the following: information indicating a location of a subframefor sending a non-periodic CSI-RS, information indicating a location ofa PRB pair for sending the non-periodic CSI-RS, information indicatingthe number of CSI-RS ports of the non-periodic CSI-RS, and informationindicating a location of a RE, which is used for sending thenon-periodic CSI-RS, in a PRB pair. In an implementation process, thefirst sending component 10 may further send the DL control signalling,which includes the transmission resource configuration information ofthe non-periodic CSI-RS, in at least one of manners as follows: sendinga notice about the information indicating the location of the subframeto the terminal through physical layer configuration signalling; sendinga notice about information indicating the location of the PRB pair tothe terminal through physical layer control signalling; sending a noticeabout the information indicating the number of CSI-RS ports to theterminal through physical layer signalling and/or RRC signalling; andsending a notice about information indicating the location of the RE,which is used for sending the non-periodic CSI-RS, in the PRB pair tothe terminal through the physical layer signalling and/or the RRCsignalling.

Based on the device for determining the indication signalling of thepilot signal for channel measurement, the embodiment of the presentdisclosure further provides a device for triggering CSI feedback. Thedevice may also be applied to a NodeB, and is configured to send CSIfeedback triggering instruction information to a terminal, and itsstructure diagram is shown in FIG. 7, including: a second sendingcomponent 20 configured to send the CSI feedback triggering instructioninformation and resource allocation information of a PDSCH to theterminal in the same control signalling format of DL control signalling,wherein the CSI feedback triggering instruction information is used forinstructing the terminal to feed back CSI.

In an implementation process, the device may further include a settingcomponent 30 configured to set a representation manner for the CSIfeedback triggering instruction information, and as shown in FIG. 8, thesetting component 30 may be coupled to the second sending component 20,wherein the setting component 30 is configured to set the CSI feedbacktriggering instruction information in one of manners as follows: settingtransmission resource configuration information of the non-periodicCSI-RS to represent the CSI feedback triggering instruction information;setting Qbit signalling in the control signalling format to representthe CSI feedback triggering instruction information; and setting apartial state bit in the control signalling format to represent the CSIfeedback triggering instruction information.

The embodiment of the present disclosure further provides a device forfeeding back a CSI. The device may be applied to a terminal, and itsstructure diagram is shown in FIG. 9, wherein the device includes: areceiving component 40 configured to receive CSI feedback triggeringinstruction information from a NodeB, wherein the CSI feedbacktriggering instruction information and resource allocation informationof a PDSCH are sent in the same control signalling format of DL controlsignalling; and a feedback component 50 coupled to the receivingcomponent 40 and configured to feed back CSI acquired according to theCSI feedback triggering instruction information to the NodeB.

FIG. 10 is an example structure diagram of the receiving component 40,wherein the receiving component 40 may further include: a firstreceiving element 402, configured to receive transmission resourceconfiguration information of the non-periodic CSI-RS from the NodeB; asecond receiving element 404 configured to receive one piece of stateinformation of preset Qbit signalling from the NodeB; and a thirdreceiving element 406 configured to receive a partial state bit set inthe control signalling format from the NodeB. The three differentreceiving elements may be configured to receive CSI feedback triggeringinstruction information under different conditions.

The feedback component 50 may feed back the CSI acquired according tothe CSI feedback triggering instruction information to the NodeB in atleast one of manners as follows: acquiring and feeding back the CSIaccording to a pilot signal for channel measurement which locates in aresource location of a non-periodic CSI-RS, wherein the non-periodicCSI-RS is a signal sent by the NodeB to instruct the terminal to performchannel measurement; acquiring and feeding back the CSI according to aperiodic CM-RS or a CRS; acquiring and feeding back the CSI according toa frequency-domain resource where the PDSCH corresponding to DCIlocates; feeding back the CSI on the Nth subframe after the CSI feedbackis triggered by the CSI feedback triggering instruction information,wherein N is a natural number more than or equal to 1, and a value of Nis a fixed integer or configured by high-layer signalling; and feedingback the CSI at a preset location in a subframe, wherein the presetlocation includes one of the following: a PUCCH for feedback and a PUSCHfor feedback on a preset bandwidth.

Example Embodiment

For the problems existing in the related art, the embodiment of thepresent disclosure provides a non-periodic CSI-RS signalling which istriggered by a physical layer signalling and a method for sending thenon-periodic CSI-RS signalling, so as to reduce CSI-RS overhead andcorresponding feedback complexity.

On a NodeB side, the NodeB sends transmission resource configurationinformation of the non-periodic CSI-RS which is carried in a physicallayer control channel, to a terminal, wherein the transmission resourceconfiguration information of the non-periodic CSI-RS includes at leastone of: (1) information indicating a location of a subframe; (2)information indicating a location of a PRB pair; (3) informationindicating the number of CSI-RS ports; and (4) information indicating anRE location of the CSI-RS in a PRB pair.

The NodeB may make an agreement on a method for determining a locationof a subframe with the terminal, and the method includes: determining alocation for sending a non-periodic CSI-RS according to the location ofthe subframe, on which physical layer configuration signalling isreceived by the terminal, and a preset rule, wherein the specificagreement rule may be set according to a practical need.

The NodeB may further notify the information indicating the location ofthe PRB pair for sending the non-periodic CSI-RS through physical layercontrol signalling, wherein the method includes that: the NodeB and theterminal make an agreement about multiple sets of locations oftransmission RBs in advance, wherein each set corresponds to one RBGroup, and one RB Group corresponds to a partial state location of DCI.The predefined multiple sets of locations of the transmission RBsinclude at least one of: (1) RB1 to RB[M/4]; (2) RB[M/4+1] to RB[M/2];(3) RB[M/2+1] to RB[3M/4]; (4) RB[3M/4+1] to RB[M]; (5) RB1 to RB[M/2];(6) RB[M/2+1] to RB[M]; (7) all RBs with odd index values; (8) all RBswith even indexes; and (9) the latest RBs transmitting a PhysicalDownlink Shared Channel (PDSCH), wherein M is the number of PRB pairscorresponding to a current bandwidth

Furthermore, the preset sets of locations of transmission RBs may alsobe preset by a protocol or agreed by the NodeB through a high-layersignalling configuration. The number of ports of the non-periodic CSI-RSand the location of the non-periodic CSI-RS in the PRB pair arejoint-coded.

The example embodiment further provides a method for triggering CSIfeedback, and in the method, the NodeB side may send CSI feedbacktriggering instruction information to the terminal. In the method, theNodeB sends the CSI feedback triggering instruction information andresource allocation information of the PDSCH in the same controlsignalling format together.

The CSI feedback triggering instruction information may be determinedaccording to whether the control signalling format contains transmissionresource configuration information of the non-periodic CSI-RS or not,for example, CSI feedback is determined to be triggered under thecondition that the transmission resource configuration information ofthe non-periodic CSI-RS is contained. When the CSI feedback istriggered, UE performs CSI calculation and feedback according to a pilotsignal for channel measurement which locates at a resource location of anon-periodic CSI-RS. Such a manner that CSI feedback is triggered by thetransmission resource configuration information of the non-periodicCSI-RS is equivalent to an implicit setting manner, and an explicitmanner is introduced below.

The CSI feedback triggering instruction information may be representedby Qbit signalling set in the sent DL control signalling, wherein onestate corresponds to non-triggering, each of the other statescorresponds to a predefined CSI calculation and feedback rule, and Q isa natural number. Or, a partial state bit may further be set torepresent the CSI feedback triggering instruction information.

When the UE on the terminal side receives the CSI feedback triggeringinstruction information, CSI feedback may be triggered.

When the CSI feedback is triggered, the UE acquires and feeds back CSIon the basis of a periodic CSI-RS or a CRS; or, when feedback istriggered, based on a frequency-domain resource where the PDSCHcorresponding to DCI locates, the UE acquires the CSI according to aDMRS corresponding to a PDSCH; or, the UE determines to acquire and feedback the CSI according to a configured feedback mode; or, the terminalfeeds back the CSI on the nth subframe after the CSI feedback istriggered by DL Grant of the DL control signalling, wherein n is a fixedinteger or configured by high-layer signalling; or, the CSI may be fedback at a preset location in a subframe, wherein the preset locationincludes one of: a PUCCH for feedback and a PUSCH for feedback on apreset bandwidth. When the feedback information of the non-periodic CSIis transmitted through the PUCCH, the CSI and A/N may be transmittedtogether.

On a terminal side, the terminal receives the DL control signalling,acquires the CSI according to the CSI feedback triggering instructioninformation in the DCI, and sends the CSI.

In an example embodiment, the terminal sends the CSI to the NodeBthrough the PUCCH or the PUSCH. If the feedback information of thenon-periodic CSI is transmitted through the PUCCH, the CSI may betransmitted together with A/N.

Furthermore, the feedback instruction information may be determinedaccording to whether the control signalling format of the DL controlsignalling contains configuration information of pilot signal forchannel measurement or not, or, non-periodic CSI-RS and feedback aresimultaneously triggered. When the feedback is triggered, the UEperforms CSI calculation and feedback according to the pilot signal forchannel measurement which locates in the resource location of thenon-periodic CSI-RS.

If the feedback instruction information is explicit Qbit signalling, afeedback manner is determined according to the received signalling. Forthe Qbit signalling, one state may be set to correspond tonon-triggering, and each of the other states may be set to correspond toa predefined CSI calculation and feedback rule, wherein Q is a naturalnumber.

Furthermore, when the feedback is triggered, the UE may further acquireand feed back the CSI on the basis of the periodic CSI-RS or the CRS.

The UE may further acquire and feed back the CSI according to thefrequency-domain resource where the PDSCH corresponding to the DCIlocates, or the acquisition and feedback of the CSI are determinedaccording to a configured feedback mode, and when the CSI feedback istriggered, the UE acquires and feeds back the CSI according to thefrequency-domain resource where the PDSCH corresponding to the DCIlocates, then the UE acquires the CSI on the basis of the DMRScorresponding to the PDSCH.

In an example embodiment, the UE on the terminal side feeds back the CSIon the nth subframe after the DL Grant of the DL control signallingtriggers the CSI feedback, and n is a fixed integer or configuredthrough high-layer signalling.

According to the example embodiment, the NodeB transmits thenon-periodic CSI-RS to the terminal, the terminal performs channelmeasurement according to the received transmitted non-periodic CSI-RS,the non-periodic CSI-RS may not be shared by multiple users or may beshared by only a few users under normal circumstances, but its overheadis lower. The non-periodic CSI-RS is not required to be configured forall terminals, and may be combined with a periodic CSI-RS as a goodauxiliary measurement means to obtain more accurate channel qualityinformation and adaptively judge a transmission technology.

The implementation mode is described below with reference to specificexamples.

Embodiment 1

Different from a periodic CSI-RS, a non-periodic CSI-RS is generallysent only on one or few subframes. A location for sending thenon-periodic CSI-RS in a PRB pair may refer to the sending Pattern ofthe periodic CSI-RS in the related art, and the difference lies in thatthe periodic CSI-RS is predetermined to be sent in the full bandwidth onthe frequency domain and periodically sent on the time domain. Thenon-periodic CSI-RS may be selectively sent either in the full bandwidthor not in the full bandwidth on the frequency domain, and may benon-periodically sent on the time domain. Since the non-periodic CSI-RSis sent only when needed, location information about the sending of thenon-periodic CSI-RS by the NodeB is required to be dynamically notifiedto a terminal.

The NodeB triggers the non-periodic CSI-RS in physical DL controlsignalling, which also includes some location information related to thenon-periodic CSI-RS. The non-periodic CSI-RS may be preferably triggeredin manners as follows:

1 bit signalling is used, 0 represents that the non-periodic CSI-RS isnot triggered, and 1 represents that the non-periodic CSI-RS istriggered; or, 2 bit signalling is used, 00 represents that thenon-periodic CSI-RS is not triggered, 01 represents that a first set ofnon-periodic CSI-RS is triggered, 10 represents that a second set ofnon-periodic CSI-RS is triggered and 11 represents that a thirdnon-periodic CSI-RS is triggered.

Resource location configuration information corresponding to each set ofnon-periodic CSI-RS may be preconfigured and notified through high-layerRRC signalling; or, may be notified by a reserved corresponding field incurrent physical layer control signalling; or, a part of resourcelocation configuration information may be sent through RRC signallingand the other part of resource location configuration information may besent by a reserved field in the physical layer control signalling.

The resource location information may preferably include one or morepieces of the following information: (1) information indicating alocation of a subframe; (2) information indicating a location a PRBpair; (3) information indicating the number of the CSI-RS ports; and (4)information indicating an RE location of the CSI-RS in a PRB pair. Theexample describes the preferred information only, but the resourcelocation information should not be limited to the abovementionedinformation.

Except an explicit manner of introducing additional signalling bits toindicate the triggering and non-triggering of the non-periodic CSI-RS,other manners may also be adopted, for example, an information field ofthe non-periodic CSI-RS may be set to be an effective value to representthe triggering of the non-periodic CSI-RS.

The location configuration information of the CSI-RS includes atime-domain location, an RB location on the frequency domain and an RElocation in an RB.

The time-domain location information may be notified in a manner asfollows: the time-domain location information may be determinedaccording to a time-domain location of a subframe on which the currentphysical layer signalling is received, for example, the subframe forsending the non-periodic CSI-RS may be 1 or 2 subframes, which arecapable of sending the CSI-RS and are closest to the current subframe,in one set of preconfigured periodic resource. The preconfiguredperiodic resource may be one set of periodic CSI-RS resources configuredby high-layer signalling, and includes periodicity and subframe locationparameters, and there are some fixed subframes which are subframescapable of sending the non-periodic CSI-RS. For example, the set ofpreconfigured periodic resource has a periodicity of 5 ms and an offsetof 1, and non-periodic CSI-RS time-domain locations corresponding tonotification signalling of different locations are shown in FIG. 11.

The time-domain location information may be determined according to thetime-domain location where the current physical layer signallingsubframe is received, the subframe for sending the non-periodic CSI-RSmay be N subframes, which are capable of sending the CSI-RS and areclosest to the current subframe, in M sets of preconfigured periodicresources, and M and N are both integers.

Or, the time-frequency location where the non-periodic CSI-RS is sentmay further be specified or configured by signalling to be a subframe onwhich the current physical layer signalling subframe is received.

Or, the time-domain location where the non-periodic CSI-RS is sent isspecified or configured by signalling to be obtained by subtracting oneor more offsets from or adding one or more offsets to the index of thesubframe on which the current physical layer signalling subframe isreceived, and the offsets are integral subframes. For example, when acurrent Transmission Time Interval (TTI) is subframe N, then a subframewhere the non-periodic CSI-RS is located is N-offset or N+offset. Theoffset is an integer, and may be specified to be 1 or 2 in advance orconfigured by high-layer signalling.

Or, the current TTI is subframe N, then the subframes where thenon-periodic CSI-RS is located are N-offset1 and N-offset2, or N+offset1and N-offset2. Offset1 and offset2 are integers, and may be specified tobe 1 or 2 in advance or configured by high-layer signalling.

The RB location on the frequency domain is notified in a manner asfollows: the RB location on the frequency domain may be notified in aDCI format or in RRC signalling, or the location on the frequency domainmay be determined by notifying a part of location in the RRC signallingand the other part of location in the DCI format.

The RB location may be notified by adopting a manner of defining RBG toreduce overhead. An RBG may be defined as follows:

RBG1 consists of the first RB to the (M/4)th RB, RBG2 consists of the(M/4+1)th RB to the (M/2)th RB, RBG3 consists of the (M/2+1)th RB to the(3M/4)th RB, RBG4 consists of the (3M/4+1)th RB to the Mth RB, RBG5consists of the first RB to the (M/2)th RB, RBG5 consists of the(M/2+1)th RB to the Mth RB, RBG7 consists of the first RB to the Mth RB,and RBG8 is a set consisting of RBs, where the PDSCH locates, in thelatest subframe (including the current subframe) on which the PDSCH istransmitted, wherein M is the number of RBs supported by a currentbandwidth, and M/4, M/2 and 3M/4 are rounded down if not being integers.

Of course, the RBGs may alternatively be defined as follows: RBG1consists of the first RB to the (M/2)th RB, RBG2 consists of the(M/2+1)th RB to the Mth RB, RBG3 consists of the first RB to the Mth RBand RBG4 is a set consisting of RBs, where the PDSCH locates, in thelatest subframe (including the current subframe) on which the PDSCH istransmitted.

Or, the RBGs may alternatively be defined as follows: RBG1 consists ofall RBs with odd indexes, RBG2 consists of all RBs with even indexes,RBG3 consists of the first RB to the Mth RB and RBG4 is a set consistingof RBs, where the PDSCH locates, in the latest subframe (including thecurrent subframe) on which the PDSCH is transmitted.

The number of ports and the RE location in the PRB pair are notified ina manner as follows: the number of ports of the non-periodic CSI-RS maybe notified through physical layer signalling, for example, the numberof ports may be notified to be 1, 2, 4 or 8 through 2 bit signalling.

The location of the non-periodic CSI-RS in the PRB pair may be notifiedthrough physical layer signalling, for example, a CSI-RS pattern wherethe non-periodic CSI-RS is located and a location of the non-periodicCSI-RS in the pattern are notified.

Alternatively, a part of the information may be notified through the RRCsignalling, and the other part of the information may be notifiedthrough the high-layer signalling. For example, the number of ports andthe pattern where the non-periodic CSI-RS is located are notifiedthrough the RRC signalling. The location in the pattern is notifiedthrough the physical layer signalling.

Alternatively, the pattern may be notified through the RRC signalling,and the number of ports and the location in the pattern may be notifiedthrough the physical layer signalling. Furthermore, a joint-codingmanner in Table 2 (joint-coding example 1 for number of ports and RElocation) may be adopted for notification.

TABLE 2 1 port,RE1 2 port,RE1,2 1 port,RE2 2 port,RE3,4 1 port,RE3 2port,RE5,6 1 port,RE4 2 port,RE7,8 1 port,RE5 4 port,RE1,2,3,4 1port,RE6 4 port,RE5,6,7,8 1 port,RE7 8 port,RE1,2,3,4,5,6,7,8 1 port,RE8—

Or, the number of ports of the non-periodic CSI-RS is specified to beminimally 2, then joint-coding changes are shown in Table 3(joint-coding example 2 for number of ports and RE location).

TABLE 3 2 port,RE1,2 2 port,RE3,4 2 port,RE5,6 2 port,RE7,84port,RE1,2,3,4 4port,RE5,6,7,8 8port,RE1,2,3,4,5,6,7,8 —

The non-periodic CSI-RS information may be sent on DL Grant of physicallayer control signalling. The DL Grant refers to a DCI format forsending resource allocation information related to a downlink datachannel, for example, the DCI formats 2B and 2C in the related artbelong to DL Grants.

The non-periodic CSI-RS resource location configuration information maybe sent together with the DL Grant. In such a manner, since thenon-periodic CSI information is always sent together with the PDSCHinformation, the RBs, where the PDSCH locates, in the subframe may beutilized as the location for sending the non-periodic CSI-RS on thefrequency domain.

The non-periodic CSI-RS resource location configuration information mayalternatively be sent together with UL Grant. In such a manner, the ULGrant may be adopted to simultaneously send the non-periodic CSI-RSresource location configuration information and perform correspondingCSI feedback triggering, and the CSI is subsequently transmitted on aPUSCH resource indicated by the UL Grant. The UL Grant refers to a DCIformat for sending resource allocation information related to an uplinkdata channel, for example, the DCI formats 0 and 4 in the related artbelong to DL Grants.

Embodiment 2

A NodeB sends a CSI-RS mainly for expecting a terminal to carry outmeasurements by virtue of the CSI-RS. For non-periodic feedback, theNodeB needs to perform non-periodic CSI triggering.

The NodeB may trigger non-periodic CSI feedback in a DL Grant, so that atime interval between CSI-RS sending and CSI feedback may be greatlyshortened, and the problem of inaccuracy caused by a time-domain channelchange is reduced; and in addition, overhead may further be reduced.

When non-periodic CSI feedback is triggered by DL Grant, multiple CSIprocesses may be predefined, and bit states of signalling are adopted torepresent different meanings, for example, 4 states of 2 bit signallingare adopted to represent non-triggering, CSI process1 triggering, CSIprocess2 triggering and CSI process3 triggering respectively.

Or, 8 states of 3 bit signalling are adopted to representnon-triggering, CSI process1 triggering, CSI process2 triggering, CSIprocess3 triggering, CSI process4 triggering, CSI process5 triggering,CSI process6 triggering, CSI process1 triggering and CSI process8triggering respectively.

The NodeB may further utilize non-periodic CSI-RS triggering as atriggering signalling for CSI feedback corresponding to the non-periodicCSI-RS. For example, provided that the NodeB notifies the sending of thenon-periodic CSI-RS and the corresponding resource location informationto UE in the DL Grant, then the UE does not require additionalsignalling notification, and feeds back corresponding CSI information onthe nth subframe after the notification according to a preset rule.

After feedback corresponding to the non-periodic CSI-RS is triggered,the terminal further performs channel measurement and CSI calculationaccording to a sending location of the non-periodic CSI-RS. The CSImainly includes Rank Indication/Precoding Matrix Indication/ChannelQuality Indication (RI/PMI/CQI), and the terminal further calculates andfeeds back PMI and CQI corresponding to each RB for the RBs for sendingthe non-periodic CSI-RS, and calculates and feeds back RI for all theRBs. It is important to note that, when the DL Grant triggers CSIfeedback, the UE may perform measurement by virtue of the non-periodicCSI-RS, and may alternatively perform channel measurement by virtue of aDMRS.

Or, the terminal further calculates and feeds back the PMI and CQIcorresponding to each RB for the RBs for sending the non-periodicCSI-RS, and calculates and feeds back the RI for all the RBs.

The terminal may also feed back the CSI on the nth subframe after the DLGrant triggers CSI feedback, and n is a fixed integer or configured byhigh-layer signalling.

The non-periodic CSI feedback information may also be fed back at apreset location in a subframe, for example, on a PUCCH or on a PUSCH ina preset bandwidth. When the non-periodic CSI feedback information istransmitted through the PUCCH, the non-periodic CSI feedback informationmay be bound together with A/N for transmission.

Embodiment 3

A sending location of a non-periodic CSI-RS is not limited to thepatterns which have already been defined at present. When thenon-periodic CSI-RS and a PDSCH of UE are sent at the same time, thenon-periodic CSI-RS may be in an area dedicated for data transmissionoutside the patterns.

Therefore, resources may be additionally developed without influence onthe configuration of a periodic CSI-RS, for example, the REs marked asblack in FIG. 12 may also be configured to transmit the non-periodicCSI-RS.

From the above, it can be seen that the embodiments of the presentdisclosure achieve technical effects as follows:

according to the embodiments of the present disclosure, the non-periodicCSI-RS is determined according to the transmission resourceconfiguration information of the non-periodic CSI-RS, and channelmeasurement is further performed according to the non-periodic CSI-RS,so that the problems of higher overhead and resource waste caused byperiodical sending of a CSI-RS in the related art may be solved,resources are saved, and sending overhead is reduced.

Obviously, those skilled in the art should know that each component orstep of the present disclosure may be implemented by a universalcomputing device, and the components or steps can be concentrated on asingle computing device or distributed on a network formed by aplurality of computing devices, and may optionally be implemented byprogrammable codes executable for the computing devices, so that thecomponents or steps may be stored in a storage device for execution withthe computing devices, or the shown or described steps may be executedin a sequence different from the sequence here under a certaincondition, or the components or steps may form each integrated circuitcomponent, or multiple components or steps therein may form a singleintegrated circuit component for implementation. As a consequence, thepresent disclosure is not limited to any specific hardware and softwarecombination.

The above is only the example embodiment of the present disclosure andnot intended to limit the present disclosure, and for those skilled inthe art, the present disclosure may have various modifications andvariations. Any modifications, equivalent replacements, improvements andthe like within the principle of the present disclosure shall fallwithin the scope of protection defined by the claims of the presentdisclosure.

INDUSTRIAL PRACTICABILITY

The technical solutions provided by the embodiments of the presentdisclosure may be applied to the field of communication, thenon-periodic CSI-RS is determined according to the transmission resourceconfiguration information of the non-periodic CSI-RS, and channelmeasurement is further performed according to the non-periodic CSI-RS,so that the problems of higher overhead and resource waste caused byperiodical sending of a CSI-RS in the related art may be solved,resources are saved, and sending overhead is reduced.

1. A method for determining indication signalling of a pilot signal forchannel measurement, comprising: sending, by a NodeB, Downlink (DL)control signalling, which comprises transmission resource configurationinformation of non-periodic Channel State Information Reference Signal(CSI-RS), to a terminal, wherein the transmission resource configurationinformation of the non-periodic CSI-RS is used for determining alocation of the non-periodic CSI-RS, and the non-periodic CSI-RS is usedfor instructing the terminal to perform channel measurement.
 2. Themethod according to claim 1, wherein the transmission resourceconfiguration information of the non-periodic CSI-RS comprises at leastone of: information indicating a location of a subframe for sending thenon-periodic CSI-RS, information indicating a location of a PhysicalResource Block (PRB) pair for sending the non-periodic CSI-RS,information indicating the number of CSI-RS ports of the non-periodicCSI-RS, and information indicating a location of Resource Element (RE),which is used for sending the non-periodic CSI-RS, in a PRB pair.
 3. Themethod according to claim 2, wherein sending, by the NodeB, the DLcontrol signalling, which comprises the transmission resourceconfiguration information of the non-periodic CSI-RS, to the terminalcomprises at least one of the following: sending, by the NodeB, a noticeabout the information indicating the location of the subframe to theterminal through physical layer configuration signalling; sending, bythe NodeB, a notice about the information indicating the location of thePRB pair to the terminal through physical layer control signalling;sending, by the NodeB, a notice about the information indicating thenumber of the CSI-RS ports to the terminal through physical layersignalling and/or Radio Resource Control (RRC) signalling; and sending,by the NodeB, a notice about the information indicating the location ofthe RE, which is used for sending the non-periodic CSI-RS, in the PRBpair to the terminal through physical layer signalling and/or RRCsignalling.
 4. The method according to claim 3, wherein a method fordetermining a location for sending the non-periodic CSI-RS comprises:determining the location for sending the non-periodic CSI-RS accordingto the information indicating the location of the subframe and a presetrule, wherein the information indicating the location of the subframe iscarried in the physical layer configuration signalling received by theterminal.
 5. The method according to claim 3, wherein sending, by theNodeB, the notice about the information indicating the location of thePRB pair to the terminal through the physical layer control signallingcomprises: presetting, by the NodeB and the terminal, multiple sets oflocations of transmission Resource Blocks (RBs), wherein each of themultiple sets of locations of transmission RBs corresponds to one RBGroup, and one RB Group corresponds to a part of state locations ofDownlink Control Information (DCI).
 6. (canceled)
 7. (canceled)
 8. Themethod according to claim 3, wherein the number of CSI-RS ports of thenon-periodic CSI-RS and the information indicating the location of theRE, which is used for sending the non-periodic CSI-RS, in the PRB pairare joint-coded.
 9. The method according to claim 1, wherein sending, bythe NodeB, the DL control signalling, which comprises the transmissionresource configuration information of the non-periodic CSI-RS, to theterminal comprises: sending, by the NodeB, the transmission resourceconfiguration information of the non-periodic CSI-RS and resourceallocation information of a PDSCH to the terminal in the same controlsignalling format of the DL control signalling; or, sending, by theNodeB, the transmission resource configuration information of thenon-periodic CSI-RS and resource allocation information of a PhysicalUplink Shared Channel (PUSCH) to the terminal in the same controlsignalling format of the DL control signalling.
 10. The method accordingto claim 1, wherein the transmission resource configuration informationof the non-periodic CSI-RS is sent in N preset subframes of the DLcontrol signalling, wherein N is an integer more than
 1. 11. A methodfor triggering Channel State Information (CSI) feedback, comprising:sending, by a NodeB, CSI feedback triggering instruction information andresource allocation information of a Physical Downlink Shared Channel(PDSCH) to a terminal in the same control signalling format of Downlink(DL) control signalling, wherein the CSI feedback triggering instructioninformation is used for instructing the terminal to feed back CSI. 12.The method according to claim 11, wherein a manner for setting the CSIfeedback triggering instruction information comprises: settingtransmission resource configuration information of non-periodic ChannelState Information Reference Signal (CSI-RS) to represent the CSIfeedback triggering instruction information; setting Qbit signalling inthe control signalling format to represent the CSI feedback triggeringinstruction information; or, setting a partial state bit in the controlsignalling format to represent the CSI feedback triggering instructioninformation.
 13. (canceled)
 14. The method according to claim 12,wherein the terminal acquires and/or feeds back the CSI in one ofmanners as follows: when the CSI feedback triggering instructioninformation triggers CSI feedback, the terminal acquiring and feedingback the CSI on the basis of a periodic CSI-RS or a Cell specificReference Signal (CRS); when the CSI feedback triggering instructioninformation triggers CSI feedback, the terminal acquiring and feedingback the CSI according to a frequency-domain resource where the PDSCHcorresponding to the DL control signalling locates; when the CSIfeedback triggering instruction information triggers CSI feedback, theterminal determining the acquisition and feedback of the CSI accordingto a feedback mode configured by the DL control signalling; when DLGrant of the DL control signalling triggers CSI feedback, the terminalfeeding back the CSI on the Nth subframe after the DL Grant triggers CSIfeedback, wherein N is a natural number more than or equal to 1, and avalue of N is a fixed integer or configured by high-layer signalling;and when the CSI feedback triggering instruction information triggersCSI feedback, the terminal feeding back the CSI at a preset location ina subframe, wherein the preset location comprises one of: a PhysicalUplink Control Channel (PUCCH) for feedback and a Physical Uplink SharedChannel (PUSCH) for feedback on a preset bandwidth.
 15. The methodaccording to claim 14, wherein the terminal acquiring and feeding backthe CSI according to the frequency-domain resource where the PDSCHcorresponding to the DL control signalling locates comprises: theterminal acquiring the CSI on the basis of a Demodulation ReferenceSignal (DMRS) corresponding to the PDSCH.
 16. (canceled)
 17. A methodfor feeding back Channel State Information (CSI), comprising: receiving,by a terminal, CSI feedback triggering instruction information from aNodeB, wherein the CSI feedback triggering instruction information andresource allocation information of a Physical Downlink Shared Channel(PDSCH) are sent in the same control signalling format of Downlink (DL)control signalling; and feeding back, by the terminal, CSI acquiredaccording to the CSI feedback triggering instruction information to theNodeB.
 18. The method according to claim 17, wherein receiving, by theterminal, the CSI feedback triggering instruction information from theNodeB comprises: receiving, by the terminal, transmission resourceconfiguration information of non-periodic Channel State InformationReference Signal (CSI-RS) from the NodeB; or, receiving, by theterminal, one piece of state information of preset Qbit signalling fromthe NodeB; or, receiving, by the terminal, a partial state bit set inthe control signalling format from the NodeB.
 19. The method accordingto claim 18, wherein feeding back, by the terminal, the CSI acquiredaccording to the CSI feedback triggering instruction information to theNodeB comprises one of the following steps: acquiring and feeding back,by the terminal, the CSI according to a channel measurement pilot at aresource location of a non-periodic CSI-RS, wherein the non-periodicCSI-RS is a signal sent by the NodeB to instruct the terminal to performchannel measurement; acquiring and feeding back, by the terminal, theCSI according to a periodic CRI-RS or a Cell specific Reference Signal(CRS); and acquiring and feeding back, by the terminal, the CSIaccording to a frequency-domain resource where a PDSCH corresponding toDownlink Control Information (DCI) locates.
 20. The method according toclaim 19, further comprising: feeding back, by the terminal, the CSI onthe Nth subframe after the CSI feedback triggering instructioninformation triggers CSI feedback, wherein N is a natural number morethan or equal to 1, and a value of N is a fixed integer or configured byhigh-layer signalling; and feeding back, by the terminal, the CSI at apreset location in a subframe, wherein the preset location comprises oneof: a Physical Uplink Control Channel (PUCCH) for feedback and aPhysical Uplink Shared Channel (PUSCH) for feedback on a presetbandwidth.
 21. (canceled)
 22. A device for determining indicationsignalling of a pilot signal for channel measurement, which is appliedto a NodeB and comprises: a first sending component, configured to sendDownlink (DL) control signalling, which comprises transmission resourceconfiguration information of non-periodic Channel State InformationReference Signal (CSI-RS), to a terminal, wherein the transmissionresource configuration information of the non-periodic CSI-RS is usedfor determining a location of the non-periodic CSI-RS, and thenon-periodic CSI-RS is used for instructing the terminal to performchannel measurement.
 23. The device according to claim 22, wherein thetransmission resource configuration information of the non-periodicCSI-RS sent by the first sending component comprises at least one of:information indicating a location of a subframe for sending thenon-periodic CSI-RS, information indicating a location of a PhysicalResource Block (PRB) pair for sending the non-periodic CSI-RS,information indicating the number of CSI-RS ports of the non-periodicCSI-RS, and information indicating a location of Resource Element (RE),which is used for sending the non-periodic CSI-RS, in a PRB pair. 24.The device according to claim 23, wherein the first sending componentsends the DL control signalling, which comprises the transmissionresource configuration information of the non-periodic CSI-RS, in atleast one of manners as follows: sending a notice about the informationindicating the location of the subframe to the terminal through physicallayer configuration signalling; sending a notice about the informationindicating the location of the PRB pair to the terminal through physicallayer control signalling; sending a notice about the informationindicating the number of the CSI-RS ports to the terminal throughphysical layer signalling and/or Radio Resource Control (RRC)signalling; and sending a notice about the information indicating thelocation of the RE, which is used for sending the non-periodic CSI-RS,in the PRB pair to the terminal through the physical layer signallingand/or the RRC signalling.
 25. A device for triggering Channel StateInformation (CSI) feedback, which is applied to a NodeB and comprises: asecond sending component, configured to send CSI feedback triggeringinstruction information and resource allocation information of aPhysical Downlink Shared Channel (PDSCH) to a terminal in the samecontrol signalling format of Downlink (DL) control signalling, whereinthe CSI feedback triggering instruction information is used forinstructing the terminal to feed back CSI.
 26. The device according toclaim 25, further comprising a setting component configured to set arepresentation manner for the CSI feedback triggering instructioninformation, wherein the setting component is configured to set the CSIfeedback triggering instruction information in one of manners asfollows: setting transmission resource configuration information ofnon-periodic Channel State Information Reference Signal (CSI-RS) torepresent the CSI feedback triggering instruction information; settingQbit signalling in the control signalling format to represent the CSIfeedback triggering instruction information; and setting a partial statebit in the control signalling format to represent the CSI feedbacktriggering instruction information.
 27. A device for feeding backChannel State Information (CSI), which is applied to a terminal andcomprises: a receiving component, configured to receive CSI feedbacktriggering instruction information from a NodeB, wherein the CSIfeedback triggering instruction information and resource allocationinformation of a Physical Downlink Shared Channel (PDSCH) are sent inthe same control signalling format of Downlink (DL) control signalling;and a feedback component, configured to feed back CSI acquired accordingto the CSI feedback triggering instruction information to the NodeB. 28.The device according to claim 27, wherein the receiving componentcomprises: a first receiving element, configured to receive transmissionresource configuration information of a non-periodic Channel StateInformation Reference Signal (CSI-RS) from the NodeB; a second receivingelement, configured to receive one piece of state information of presetQbit signalling from the NodeB; and a third receiving element,configured to receive a partial state bit set in the control signallingformat from the NodeB.
 29. The device according to claim 28, wherein thefeedback component feeds back the CSI acquired according to the CSIfeedback triggering instruction information to the NodeB in at least oneof manners as follows: acquiring and feeding back the CSI according to achannel measurement pilot at a resource location of a non-periodicCSI-RS, wherein the non-periodic CSI-RS is a signal sent by the NodeB toinstruct the terminal to perform channel measurement; acquiring andfeeding back the CSI according to a periodic CRI-RS or a Cell specificReference Signal (CRS); acquiring and feeding back the CSI according toa frequency-domain resource where a PDSCH corresponding to DownlinkControl Information (DCI) locates; feeding back the CSI on the Nthsubframe after the CSI feedback triggering instruction informationtriggers CSI feedback, wherein N is a natural number more than or equalto 1, and a value of N is a fixed integer or configured by high-layersignalling; and feeding back the CSI at a preset location in a subframe,wherein the preset location comprises one of: a Physical Uplink ControlChannel (PUCCH) for feedback and a Physical Uplink Shared Channel(PUSCH) for feedback on a preset bandwidth.